diff --git a/core/modules/layout_builder/src/Form/OverridesEntityForm.php b/core/modules/layout_builder/src/Form/OverridesEntityForm.php
index 29f940bdcc..789778fc8f 100644
--- a/core/modules/layout_builder/src/Form/OverridesEntityForm.php
+++ b/core/modules/layout_builder/src/Form/OverridesEntityForm.php
@@ -198,6 +198,8 @@ class OverridesEntityForm extends ContentEntityForm {
       '#value' => $this->t('Discard changes'),
       '#submit' => ['::redirectOnSubmit'],
       '#redirect' => 'discard_changes',
+      // Discard is not dependent on form input.
+      '#limit_validation_errors' => [],
     ];
     // @todo This button should be conditionally displayed, see
     //   https://www.drupal.org/node/2917777.
diff --git a/core/modules/layout_builder/tests/src/Functional/LayoutBuilderFormModeTest.php b/core/modules/layout_builder/tests/src/Functional/LayoutBuilderFormModeTest.php
new file mode 100644
index 0000000000..b29b153a56
--- /dev/null
+++ b/core/modules/layout_builder/tests/src/Functional/LayoutBuilderFormModeTest.php
@@ -0,0 +1,107 @@
+<?php
+
+namespace Drupal\Tests\layout_builder\Functional;
+
+use Drupal\Core\Entity\Entity\EntityFormMode;
+use Drupal\Core\Url;
+use Drupal\entity_test\Entity\EntityTest;
+use Drupal\field\Entity\FieldConfig;
+use Drupal\field\Entity\FieldStorageConfig;
+use Drupal\Tests\BrowserTestBase;
+
+/**
+ * Tests Layout Builder forms.
+ *
+ * @group LayoutBuilderFormTest
+ */
+class LayoutBuilderFormModeTest extends BrowserTestBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  protected static $modules = [
+    'field',
+    'entity_test',
+    'layout_builder',
+  ];
+
+  /**
+   * {@inheritdoc}
+   */
+  protected $defaultTheme = 'classy';
+
+  /**
+   * Tests using 'Discard changes' button skips validation and ignores input.
+   */
+  public function testDiscardValidation() {
+    $entityTypeId = 'entity_test';
+    $bundle = 'entity_test';
+
+    // Set up a field with a validation constraint.
+    $fieldStorage = FieldStorageConfig::create([
+      'field_name' => 'foo',
+      'entity_type' => $entityTypeId,
+      'type' => 'string',
+    ]);
+    $fieldStorage->save();
+
+    FieldConfig::create([
+      'field_storage' => $fieldStorage,
+      'bundle' => $bundle,
+      // Expecting required value.
+      'required' => TRUE,
+    ])->save();
+
+    /** @var \Drupal\Core\Entity\EntityDisplayRepositoryInterface $displayRepository */
+    $displayRepository = \Drupal::service('entity_display.repository');
+
+    // Enable layout builder custom layouts.
+    $displayRepository->getViewDisplay($entityTypeId, $bundle, 'full')
+      ->enable()
+      ->setThirdPartySetting('layout_builder', 'enabled', TRUE)
+      ->setThirdPartySetting('layout_builder', 'allow_custom', TRUE)
+      ->save();
+
+    // Add the form mode and show the field with a constraint.
+    $formMode = 'layout_builder';
+    EntityFormMode::create([
+      'id' => sprintf('%s.%s', $entityTypeId, $formMode),
+      'targetEntityType' => $entityTypeId,
+    ])->save();
+    $displayRepository->getFormDisplay($entityTypeId, $bundle, $formMode)
+      ->setComponent('foo', [
+        'type' => 'string_textfield',
+      ])
+      ->save();
+
+    $user = $this->drupalCreateUser([
+      'view test entity',
+      'configure any layout',
+      "configure all $entityTypeId $bundle layout overrides",
+    ]);
+    $this->drupalLogin($user);
+
+    $entity = EntityTest::create();
+    $entity->save();
+
+    $urlParameters = ['entity_test' => $entity->id()];
+    $url = Url::fromRoute('layout_builder.overrides.entity_test.view', $urlParameters);
+
+    $session = $this->assertSession();
+
+    // When submitting the form normally, a validation error should be shown.
+    $this->drupalGet($url);
+    $session->fieldExists('foo[0][value]');
+    $session->elementAttributeContains('named', ['field', 'foo[0][value]'], 'required', 'required');
+    $this->drupalPostForm(NULL, [], 'Save layout');
+    $session->pageTextContains('foo field is required.');
+
+    // When Discarding changes, a validation error will not be shown.
+    // Reload the form for fresh state.
+    $this->drupalGet($url);
+    $this->drupalPostForm(NULL, [], 'Discard changes');
+    $session->pageTextNotContains('foo field is required.');
+    $session->addressEquals(Url::fromRoute('layout_builder.overrides.entity_test.discard_changes', $urlParameters)->toString());
+  }
+
+}